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A major nemesis for growers is white mold (Sclerotinia sclerotiorum), causing devastating losses in dry bean, soybean, sunflower, canola, potato and all forage legume across the upper Midwest and Eastern corn-belt. Peanut and alfalfa are affected in the Southeast. 100% of dry bean acreage can be at risk from white mold, with yield losses as high as 50%. Losses can be 100% for irrigated acres in California and the Northwest. Chemical fungicides at best suppress infection by about 50% and have high mammalian toxicity; i.e., most are known or suspected carcinogens. Summerdale, Inc. has identified novel synergistic relationships between fatty and organic acids with preliminary efficacy shown against white mold in laboratory and initial field trials. Early cost and performance of the experimental formulations match or exceed commercial fungicides such as Topsin M, a known animal carcinogen. Phase I will examine formulation improvements on dry bean varieties in two geographic locations and characterize cost and performance advantages over commercial products. <P>Specifically, key objectives for Phase I are: <OL> <LI> further development of fungicides, containing only natural, environmentally-compatible ingredients, that are stable as formulation concentrates and as working solutions in water <LI> evaluation of characteristics (cost/performance) and other advantages versus current products for effective control of white mold to meet both conventional and organic grower requirements. </OL>The industry is actively seeking a safer, less costly and more effective method to control white mold infestations. Many if not most of the existing products have high chronic toxicity, with some suspected human carcinogens and others, toxic to birds, fish and beneficial insects. Some products will not be re-registered or their use may eventually be severely restricted under the Food Quality Protection Act, thereby creating a demand for safer products to meet grower needs. Therefore, a clear opportunity exists for alternatives with cost and performance characteristics competitive with or exceeding current products for traditional and also for rapidly expanding organic markets. Several agricultural product companies have expressed interest. Since all formulation ingredients can be obtained from renewables, in lieu of being derived
NON-TECHNICAL SUMMARY: Phaseolus dry beans are the leading grain legume crop with an annual world production of 20 million metric tons (mmt) and the U.S. is the leading export nation marketing 40% (0.4 mmt) of all dry bean production overseas. Dry or dry edible beans (DEB) are produced in the U.S. on 1.7 million acres by nearly 11,000 farms with estimated sales at $1.8 billion. Production occurs in fourteen states and includes fifteen different varieties of beans. However, dry bean diseases can dramatically reduce yield, quality of harvested beans and therefore, greatly affect grower profits. White mold in particular is a key pest of dry beans in Michigan. Serious losses can occur when weather conditions are favorable for disease development and disease organisms are present. Except for the driest seasons, 100% of crop acres are at risk and up to 40-50% can be affected, with yield losses as high as 50% occurring within 2 weeks late in the growing season. Under irrigated production in California and the Northwest, losses can be 100%. Intervention with chemical treatments at early flowering suppresses white mold but does not completely eradicate the disease. Generally growers are delighted to obtain 50% suppression of white mold with a single fungicide application but of course, growers also expect to have a yield increase over untreated crops. An additional spray treatment can provide extra protection but more often than not, two applications of current fungicide products for dry bean is cost prohibitive. Identifying a novel fungicide that is cost-effective for two applications would be highly advantageous; especially for use in fields with a history of disease and during periods of prolonged and/or heavy rainfall particularly at time of flowering. Moreover, nearly all labeled fungicides are listed as carcinogens or suspected carcinogens and some have high chronic toxicity. Many are either highly toxic to fish/ aquatic life (Topsin, Blocker 4F, Switch) or have issues of pathogen resistance (Rovral, Endura and Switch). Topsin-M, Rovral and Ronilan are on the California list of "Known Carcinogens and Reproductive Toxicants". Blocker 4F is listed in California as a toxic air contaminant. Due to the serious health and safety issues related to these products, re-registration under the Food Quality Protection Act (FQPA) could be jeopardized or severe restrictions could be implemented. Hence, growers seek safer, less costly products to effectively control white mold infestations. It is anticipated that EPA registration for most, if not all, of the experimental ingredients will likely include acute toxicity testing and minimal (if any) chronic toxicity trials on animals; i.e., teratogenic and carcinogenic studies. Use of more environmentally friendly products by growers would lower consumer risk. The discovery of alternative chemicals that protect food safety would agree with some of the goals for sustainable agriculture and protect quality of life. Pesticides obtained from renewables and not derived from petrochemicals would also be in the public interest. <P>APPROACH: A research team is already in place to complete all of the necessary tasks. The research team will include Robert Coleman (Summerdale, Inc.), Robert Harveson, Associate Professor/Plant Pathologist at the University of Nebraska, Greg Varner at the MSU Michigan Agricultural Experimental Station, Saginaw Valley Bean and Sugar Beet Research Farm, Saginaw MI and support staff at all institutions. Greg Varner is the research director for the Michigan Dry Bean Production Research Advisory Board in Saginaw, MI. <P>Key objectives for Phase I include demonstration that one or more selected formulations, when compared to commercial products, is (are): a) as effective or more effective, when used as single (or dual) applications, b) comparable or less expense to the grower and c) effective for several classes/varieties of dry bean. <P>Specific Phase I technical objectives and milestones are the following: <OL> <LI> Formulate selected combinations of fatty acid, emulsifier, synergist (organic acid) and adjuvant (sticker) and in turn, identify formulations having the greatest stability as concentrates and as dilutions of concentrates in water (R. Coleman): Month 1 <LI>Determine lowest, feasible application rate for control of white mold on dry bean: complete rate studies of formulations developed in objective #1 and evaluate required frequency of use; i.e., one versus two applications. Compare with commercial products per fungicidal activity on at least two dry bean classes (G. Varner, R. Harveson and R. Coleman): Months 2 - 6 <LI> Evaluate and summarize performance, cost characteristics and other advantages of best experimental formulation (s) relative to commercial products (R. Coleman): Month 6 <LI> Obtain comment and recommendations from trade associations, university extensions and potential end-users pertaining to Phase I field trial results (R. Coleman): Month 6